一句话:该论文提出推理框架相对渐近表达力的预序,证明两个新的公式渐近等价结果并给出收敛律推论。
论文研究如何比较概率推理框架的表达力。此类框架由有限结构上的概率分布序列与在[0,1]中取真值的逻辑组成。作者将公式的几乎必然等价推广为渐近等价,并据此定义框架间的相对渐近表达力:若一个框架能用另一框架的分布和公式渐近地模拟,则后者至少同样表达力,该关系构成预序。论文证明两个关于公式渐近等价的新结果,各以收敛律为推论;最后将新结果与若干已有结果系统化,得到机器学习与人工智能中多个推理系统之间的表达力预序。
We consider logics with truth values in the unit interval $[0,1]$. Such logics are used to define queries and to define probability distributions. In this context the notion of almost sure equivalence of formulas is generalized to the notion of asymptotic equivalence. We prove two new results about the asymptotic equivalence of formulas where each result has a convergence law as a corollary. These results as well as several older results can be formulated as results about the relative asymptotic expressivity of inference frameworks. An inference framework $\mathbf{F}$ is a class of pairs $(\mathbb{P}, L)$, where $\mathbb{P} = (\mathbb{P}_n : n = 1, 2, 3, \ldots)$, $\mathbb{P}_n$ are probability distributions on the set $\mathbf{W}_n$ of all $\sigma$-structures with domain $\{1, \ldots, n\}$ (where $\sigma$ is a first-order signature) and $L$ is a logic with truth values in the unit interval $[0, 1]$. An inference framework $\mathbf{F}'$ is asymptotically at least as expressive as an inference framework $\mathbf{F}$ if for every $(\mathbb{P}, L) \in \mathbf{F}$ there is $(\mathbb{P}', L') \in \mathbf{F}'$ such that $\mathbb{P}$ is asymptotically total variation equivalent to $\mathbb{P}'$ and for every $\varphi(\bar{x}) \in L$ there is $\varphi'(\bar{x}) \in L'$ such that $\varphi'(\bar{x})$ is asymptotically equivalent to $\varphi(\bar{x})$ with respect to $\mathbb{P}$. This relation is a preorder. If, in addition, $\mathbf{F}$ is at least as expressive as $\mathbf{F}'$ then we say that $\mathbf{F}$ and $\mathbf{F}'$ are asymptotically equally expressive. Our third contribution is to systematize the new results of this paper and several previous results in order to get a preorder on a number of inference systems that are of relevance in the context of machine learning and artificial intelligence.
@article{paperbot2710,
title = {On the relative asymptotic expressivity of inference frameworks},
author = {Vera Koponen and Felix Weitkämper},
journal = {Logical Methods in Computer Science},
volume = {Volume 20, Issue 4},
year = {2024},
doi = {10.46298/lmcs-20(4:13)2024}
}